1. Field of the Invention
The invention relates to a video recorder for the reproduction of video recordings recorded on magnetic tapes, these recordings being available with different playback qualities, comprising reproduction means for scanning a magnetic tape and for supplying a playback signal representing a video recording, and playback-signal processing means for processing the playback signal and including at least one controllable signal-influencing stage for controllably influencing at least one component of the playback signal.
2. Description of the Related Art
Such a video recorder of the type defined in the opening paragraph is known, for example, from European Patent Specification EP 0 464 772 B1, corresponding to U.S. Pat. No. 5,257,109, and divisional U.S. Pat. No. 5,249,064, 5,400,149, 5,416,641 and 5,446,539. In this known video recorder, the playback-signal processing means comprises several signal-influencing stages, such as an FM equalizer stage, a peaking stage, a horizontal noise cancellation stage and a vertical noise cancellation stage, which are controllable with the aid of control means so as to change their signal-influencing qualities, the control means controlling said stages in dependence upon the characteristics of different magnetic tapes, thereby enabling said stages to be adapted to different characteristics or properties of different magnetic tapes in order to achieve an optimum reproduction of video recordings made on magnetic tapes having different properties. By means of the known video recorder, it is possible to achieve a correct reproduction of video recordings from magnetic tapes having different characteristics or properties. However, apart from this advantageous feature, this known video recorder has a limitation as a result of which a wholly satisfactory reproduction of video recordings is not guaranteed in some cases.
It is an object of the invention to avoid the aforementioned limitation and to provide an improved video recorder of the type defined in the opening paragraph. To this end, according to the invention, a video recorder of the type defined in the opening paragraph is characterized in that there have been provided entry means which cooperates with the video recorder and which is adapted to enter characteristic information which characterizes different playback qualities of video recordings, and the video recorder includes control means arranged to receive the characteristic information and adapted to generate control information corresponding to the characteristic information, and the at least one controllable signal-influencing stage is adapted to be controlled in respect of its controllable influencing of at least one component of the playback signal in dependence upon the control information generated by the control means. Thus, it is achieved with simple means and with only a very small additional expenditure, that the at least one controllable signal-influencing stage for controllably influencing a playback signal can be adapted to different playback qualities of video recordings in an easy manner, and in accordance with the wishes and requirements of a user of the video recorder, by the playback-signal processing means which includes said stage. In principle, the different playback qualities of video recordings are determined by the relevant program material, i.e., whether it is a video recording which has never been played before, or a video recording which has been played very frequently, for example, a rental cassette, or a video recording in the form of an animated cartoon, or a studio-quality video recording made in a studio by high-quality video cameras, or a lower quality but very up-to-date reporter""s video recording made by a portable camera, or a sports video recording. When a user introduces a magnetic tape, which for this purpose is accommodated in a cassette, into a video recorder in accordance with the invention, the user practically always knows the playback quality of the video recording made on the introduced magnetic tape, as a result of which, the user can select a setting corresponding to this playback quality for the at least one controllable signal-influencing stage of the playback-signal processing means with the aid the entry means, after which the control means included in the video recorder automatically controls the at least one controllable signal-influencing stage of the playback-signal processing means in accordance with the user""s wishes.
In a video recorder in accordance with the invention having the characteristic features described above, it has proven to be advantageous, in addition, that the playback-signal processing means includes a plurality of controllable signal-influencing stages for controllably influencing at least one component of the playback signal, and all the controllable signal-influencing stages are controllable in dependence upon control information generated by the control means. In this way, it is achieved that by merely entering characteristic information using the entry means, the user of the video recorder can simply and particularly reliably control a plurality of signal-influencing stages for an optimum reproduction of a video recording having a given playback quality and set these stages to the best possible influencing mode.
In such a video recorder in accordance with the invention, it has proven to be very advantageous, in addition, that the video recorder further comprises input means for receiving the control information generated by the control means, and for deriving stage control information corresponding to the control information, the stage control information being applied to the signal-influencing stages for controlling the manner in which the signal-influencing stages influence the at least one component of the playback signal. Tests have proven that such an embodiment is particularly advantageous for controlling a plurality of signal-influencing stages in an as simple and reliable as possible manner.
In such a video recorder in accordance with the invention, it has prove to be very advantageous, in addition, that the playback-signal processing means includes an FM equalizer stage, a vertical noise-cancellation stage, a first horizontal noise-cancellation stage, a second horizontal noise-cancellation stage, and a picture-sharpness control stage, wherein each of these five signal-influencing stages receives stage control information via the input means. With such an embodiment, the signal-influencing stages in the playback-signal processing means can be adapted to different playback qualities of video recordings in a particularly suitable and differentiated manner.
In such a video recorder in accordance with the invention, it has proven to be particularly advantageous, in addition, that the five signal-influencing stages are realized in an integrated device connected to the control means via a bus line forming part of the input means. This is particularly advantageous for a simple construction and for a simple and faultless control of the controllable signal-influencing stages.
In a video recorder in accordance with the invention having the characteristic features described above, it has further proven to be very advantageous, in addition, that the entry means enters first characteristic information characterizing the playback quality of a video recording being played for the first time or having been played only a few times, and second characteristic information characterizing the playback quality of a video recording having already been played many times. In this way, it is achieved that the user can simply adapt the at least one controllable signal-influencing stage in the playback-signal processing means to the playback quality of a video recording which is played for the first time or which has been played only a few times, as well as to the playback quality of a video recording which has already been played many times, as, for example, recorded on the magnetic tape of a so-called rental cassette.
In such a video recorder in accordance with the invention, it has proven to be very advantageous, in addition, that the entry means, in addition, enters third characteristic information representing the playback quality of a video recording of an animation film. Such an embodiment, in addition, enables the at least one controllable signal-influencing stage in the playback-signal processing means to be adapted to the playback quality of a video recording representing a trick film.
In such a video recorder in accordance with the invention, it has proven to be very advantageous, in addition, that the entry means, in addition, enters at least one further item of characteristic information. In this way, the at least one controllable signal-influencing stage in the playback-signal processing means can, in addition, be adapted to at least one further playback quality of video recordings.
The aforementioned aspects as well as further aspects of the invention will be apparent from the embodiment described hereinafter by way of example and will be elucidated on the basis of this embodiment.